Elastic and anelastic properties of SiC/Si ecoceramics

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Vol. 442; no. 1; pp. 444 - 448
• Main Authors: Kardashev, B.K., Smirnov, B.I., de Arellano-Lopez, A.R., Martinez-Fernandez, J., Varela-Feria, F.M.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 20.12.2006
• Subjects: Adsorption–desorption; Amplitude dependences; Biomorphic SiC/Si ceramics; Carbon bio-matrix; Microplastic deformation; Young's modulus; Carbon bio-matrix; Young's modulus; Biomorphic SiC/Si ceramics; Amplitude dependences; Microplastic deformation; Adsorption–desorption
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2006.02.221

The paper represents an acoustic investigation of elastic and anelastic properties of a new class of materials produced with natural (wood) products—biomorphic SiC/Si (bio-SiC/Si) ceramics. Specimens were fabricated by melt Si infiltration in a carbon bio-matrix after the wood (white eucalyptus) templates pyrolysis. It has been found that there exist, at least, two mechanisms that influence the elastic and anelastic properties of bio-SiC/Si. The first one is adsorption and/or desorption of air molecules (presumably because of the pores and residual carbon). The second one is associated with a microplastic deformation that is due to dislocations or any other structural entities which can oscillate under ultrasonic stresses and, in this way, increase both the damping and non-linear anelastic strain. The eucalyptus carbon bio-matrix has also been studied.